New tire question

Okay I ordered a set of veloflex tires on ebay, and got home to put them on today, and I noticed that the instructions said to mount on a 622x13 rim.
My bontrager x lites happen to be 622x15.
I did manage to get them on with a moderate level of difficulty, and I got them aired up and all, but they're tight as heck.
Anyone ever rode with tire variation like this before with any success? or am I looking at pinch flats all over the place or rim damage?
Thanks.